Arruda-Boyce
The Arruda-Boyce material model is described in terms of the strain energy potential, W, as follows:
where
![](../../../../../simulate/simulate/images/mu.gif)
is the initial shear modulus.
![](../../../../../simulate/simulate/images/lambda_m.gif)
is the limiting network stretch.
![](../../../../../simulate/simulate/images/arruda_boyce_d.gif)
is the incompressibility parameter.
where K is the initial bulk modulus.
![](../../../../../simulate/simulate/images/arruda_boyce_i1.gif)
is the first deviatoric strain invariant defined as follows:
where the deviatoric stretches are given as follows:
J is the total volumetric ratio.
![](../../../../../simulate/simulate/images/arruda_boyce_je.gif)
is the elastic volume ratio given by
where
![](../../../../../simulate/simulate/images/arruda_boyce7.gif)
.
where
![](../../../../../simulate/simulate/images/arruda_boyce_alpha.gif)
is the coefficient of thermal expansion.
T is the model temperature.
T0 is the reference temperature.
When you select
Arruda-Boyce material model
to define the hyperelastic material, you must specify values for
![](../../../../../simulate/simulate/images/mu.gif)
(mu),
![](../../../../../simulate/simulate/images/lambda_m.gif)
(lambda_m), and
![](../../../../../simulate/simulate/images/arruda_boyce_d.gif)
. The value of lambda_m must be greater than 1.
For materials that are nearly incompressible,
Creo Simulate uses incompressibility conditions. If the specified value of D is less than
![](../../../../../simulate/simulate/images/arruda_boyce8.gif)
,
Creo Simulate uses following value of D during analysis:
D =
![](../../../../../simulate/simulate/images/arruda_boyce8.gif)
.
where G is the initial shear modulus.
Creo Simulate calculates these coefficients when you select
Arruda-Boyce material model on the
Hyperelastic Material Definition dialog box. If you provide insufficient stress-strain data in the test area,
Creo Simulate can not generate best fit curve for
Arruda-Boyce material model and can not calculate the coefficients.